US President-elect Donald Trump says he will nominate an official known for his hardline stance toward China for a senior post at the Defense Department.

Trump announced on Sunday that he has picked Elbridge Colby for the post of Under Secretary of Defense for Policy.

Colby was involved in drafting defense strategies during Trump's first term. He has been insisting that the United States should focus on countering China's rapid military buildup.

When NHK interviewed him in May, Colby said Japan's efforts to increase its defense capability are heading in the right direction but are progressing too slowly.

He called on Japan to raise its defense budget to around 3 percent of gross domestic product.

Trump described Colby as a "highly respected advocate for our America First foreign and defense policy."

The president-elect also announced that he will name financier Stephen Feinberg as Deputy Secretary of Defense, the number two post at Pentagon.

Feinberg is the co-CEO of US investment fund Cerberus Capital Management.